ns of chemistry. This
so-called "wish" becomes the unit of psychology, replacing the older
unit commonly called "sensation," which latter, it is to be noted, was a
_content_ of consciousness unit, whereas the "wish" is a more dynamic
affair.

Unquestionably the mind is somehow "embodied" in the body. But how?
Well, if the unit of mind and character is a "wish," it is easy enough
to perceive how it is incorporated. It is, this "wish," something which
the body as a piece of mechanism can do--a course of action with regard
to the environment which the machinery of the body is capable of
carrying out. This capacity resides clearly in the parts of which the
body consists and in the way in which these are put together, not so
much in the matter of which the body is composed, as in the forms which
this matter assumes when organized.

In order to look at this more closely we must go a bit down the
evolutionary series to the fields of biology and physiology. Here we
find much talk of nerves and muscles, sense-organs, reflex arcs,
stimulation, and muscular response, and we feel that somehow these
things do not reach the core of the matter, and that they never can;
that spirit is not nerve or muscle; and that intelligent conduct, to say
nothing of conscious thought, can never be reduced to reflex arcs and
the like--just as a printing press is not merely wheels and rollers,
and still less is it chunks of iron. The biologist has only himself to
thank if he has overlooked a thing which lay directly under his nose. He
has overlooked the _form of organization_ of these his reflex arcs, has
left out of account that step which assembles wheels and rollers into a
printing press, and that which organizes reflex arcs, as we shall
presently see, into an intelligent, conscious creature. Evolution took
this important little step of organization ages ago, and thereby
produced the rudimentary "wish."

Now in the reflex arc a sense-organ is stimulated and the energy of
stimulation is transformed into nervous energy, which then passes along
an afferent nerve to the central nervous system, passes through this and
out by an efferent or motor nerve to a muscle, where the energy is again
transformed and the muscle contracts. Stimulation at one point of the
animal organism produces contraction at another. The principles of
irritability and of motility are involved, but all further study of
_this_ process will lead us only to the physics and chemistr